In recent years, a study of a light emitting device using an LD as a light source, or the like has been popular. Laser light which is generated from the LD has high directivity, and there is a possibility of damaging retina when being input to human eyes. For this reason, it is necessary to devise a technology in which laser light which is generated from the LD is not leaked to the outside of a device as far as possible.
In addition, in an electronic endoscope device which is disclosed in PTL 1, a detecting resistor for detecting a breakage or a short circuit of a power line is inserted into the power line, and energization of an LD is cut off based on a comparison result between a detection potential by the detecting resistor and a reference potential.
In addition, in a laser unit which is disclosed in PTL 2, a strain amount which occurs in a light guiding path through which laser light passes is detected, and energization of an LD is cut off based on the detection result.
In addition, in a light emitting device which is disclosed in PTL 3, an LD is provided in sealing means, ambient air which comes into the sealing means is detected, and energization of the LD is cut off based on the detection result.
In addition, in a light source unit which is disclosed in PTL 4, emission of harmonic light to the outside of a device is prevented using falling of a temperature of a second harmonic generation element by separating the second harmonic generation element which emits the harmonic light by converting a wavelength of laser light from a heater which controls the temperature thereof. In addition, a wavelength conversion efficiency from the laser light to the harmonic light in the second harmonic generation element is decreased when the temperature falls.
In addition, a light source device which is disclosed in PTL 5 includes a package configured by a first structure body and a second structure body for accommodating a light source unit, a package wiring unit is formed on the surface of the first structure body, a breakage of the package wiring unit is detected in a detecting circuit, and energization of the light source unit is cut off.